Well drilling



ug.A 2l, 1928. w. SHELDON WELL DRILLING Filed Sept. 24, 1924 3 She'ets- Sheet 2 ww /Mdm B ein-ATroRNEY Aug. 2l, 1928.

. 1,681,501 W. SHELDON WELL DRILLI'NG Filed Sept. 24, 1924 3 Sheets-Sheet 3 6 J8 f J9 Z7 l 97 y: g

x 1 E l* Z9 4l il l ANL BY M ATTORNEY Patented Aug. 21, 1928.

UNITED STATES l 1,681,501 PATENT OFFICE.

WALDO SHELDON, F GREENWICH; CONNECTICUT.

WELL DBILLING.

Application filed September 24, 1924. Serial No. 739,495.

This invention relates to well drilling apparatus of the type in which the drill stem 1s operated by a so-called rotary or rotary table mounted in fixed relation substantially at the level of the drill floor.

Special objects of the invention are to provide power mechanism particularly adaptable to apparatus of this type for effecting a positive feed of the drill stem l0 and which will be of simple, substantial,

compact, lpractical construction, readily installed and easily removable.

A further special object is to provide va power feed for rotaries which can be used l with facility to make and break joints in the drill stem.

The foregoing and other desirable objects are attained in this invention by certain novel features of'construction, combination and relation of parts as set forth in the following specification.

The drawings accompanying and forming part of this specification illustrate certain practical embodiments of the invention but it should be understood that the structure x may be modified and chan ed in various respects without departure 'om the broad spirit and scope of the invention as hereinafter defined and claimed. l

Figure 1 is a half sectional side elevation of the complete rotary.

Figure 2 is a top plan view of the same. Figure 3 is a cross sectional view on substantially the plane of line 3 3 of Figure 1. Figure 4 is a fragmentary view similar to Figure 1 showing the use of the invention for coupling and uncoupling the joints in the drill stem.

Figure 5 is a fragmentary plan view of.

parts shown in Figure 4.

The rotary table 5 is here shown of special construction with an elongated bearing sleeve 6 journaled in the elongated bearing 7 of the supporting base 8. This base is shown as carried by a base plate 9 supported on I-beams 10 spaced apart a distance such as to enable the entire apparatus being withdrawn through the sea-t 11 provided in the base plate. The base is steadied in the present disclosure by direct engagement with the upper and lower -flanges of the I-beams through the medium of lugs or projections 12, 13, shown in Figure I as directly en-l gaging the upper an lower iianges respectively.

At the top the rotary is preferably supported on a tapered roller or ball bearing 14 and a reversely arranged roller, ball or plain bearing 15 is provided between the lower end of the bearing and the sleeve of the table. This construction centralizes the rotary and enables it to carry both lifting and lowering loads without undue friction.

Withln the bore of the table a drill stem driving sleeve 16 is slidingly keyed as by means of keys 17 seating in a key-way 18 in the table and slidingly received in a key groove 19 in the sleeve. The heads of these keys may be exposed at the top of the table or said keys may be otherwise made readily removable so that the drive sleeve may be uncoupled from the table. The adapters and slips` or other drill stem engaging devices, such as the collet chucks disclosed in my co. pending application, Serial #736,206, are mounted in the upper end of this drive in the dotted lines at 20 sleeve, as indicated in Figure 1.

The power cylinder by which the feed of the control is effected, is of annular construction, concentric with the table and defined by the annular outer and inner cylinder walls 21, 22, connected at the bottom by the annular cylinder head 23, the upper cylinder head being in the form of an annular iange 24. The piston rod 25 is of annular form sliding in between the annular upper head 24 and inner wall 22 of the cylinder and connected at its lower end to the annular head 26 operating within the annular chamber of the cylinder.

The piston is prevented from turning within the cylinder'in the present disclosure by a key or keys 27 shown detachably secured by screws 28 on the inside wall of 95 the cylinder and received in a groove or oove-ways 29 on the inside of the annuar piston rod. This construction prevents the piston from turning within the cylinder, but at the same time, permits ready se ara- 100 tion of these parts upon removal o the keys 27.

The annular cylinder is shown as of less diameter than the bore of the table and as removably supported at the lower end of 105 the bearing by a screw joint at 30, so that upon unscrewmg this cylinder, the cylinder and piston can be lifted out of the rotary as a complete assembled unit. This construction therefore enables the entire cyl- 11o inder assembly to be lifted up out of the rotary and permits of the ready substitution of onepower device for another.

A relatively rotatable power transmitting connection is provided between the piston and drive sleeve comprising in the present disclosure, the upwardly and downwardly facing thrust bearings 31 and 32, interposed between the outwardly extended flanges 33, 34 of the piston rod and the inwardly eX- tended flanges 35, 36 at the upper and lower ends respectively of the drive sleeve. This construction enables the piston to transmit both lifting and lowering forces to the drive sleeve without interfering with the free rotation of the sleeve or its sliding driven enga ement with the table.

s the entire power system seats within the rotary and is supported from the base of the rotary, it can be made very compact it can be easily lowered into place or lifted out through the top of the table and the weight of the cylinder at the bottom in effect balances the weight of the drive sleeve in its extended relation as indicated in Figure 1 so that the parts run true and free at all times without vibration or strain. Hydraulic or other power may be employed in the cylinder, connections being made with the cylinder above and below the piston as at 37 and 38A'under control of suitable valve mechanism. The table is rotated from a suit-able source of power as by means of the bevel gearing shown at 39 in Figures 1 and 2.

To enable the coupling and uncoupling of the pipe sections, provision is made for attaching pipe tongs to the table and drive sleeve respectively and holding the drive sleeve stationary while turning the table. These features are illustrated particularly in Figure 4 where one pair of tongs is shown at 40 engaged with one section 41 of the drill pipe and having a bearing against a temporary post 42 on the table, and another pair of tongs is shown at 43 engaged with another section 44 of the drill pipe and connected with the drill sleeve by a temporarily mounted post or bracket 45. nder these circumstances the keys 17 which couple the drive sleeve to the table are withdrawn from their seats at 18 so that the table will be free to turn without the sleeve and the sleeve is secured against rotation, in the present showing by dropping one or more keys 46 through openings 47 in the head of the sleeve down into seats 48 in the upper end of the annular piston rod. As the piston rod is keyed within the power cylinder, the drive sleeve will thus be temporarily held against rotating and the table may then be driven in either direction to make or break the pipe joints.

The screw connection by which the annular cylinder is removably supported by thetable bearing, is shown in Figure 1 in the form of an internally threaded ring forming a screw seat for the correspondingly threaded head of the cylinder and seated in a twopart clamp 49 held engaged with a groove 50 in the lower end of the bearing by the bolts 5,1. When the parts are assembled the screw seat ring and cylinder may be held against accidental rotation as by means of one or more shearing pins indicated at 52 driven through the clamp ring and screw ring into the upper head of the cylinder. The rotary may be utilized to break or start the cylinder from its screw seat by leaving inthe key 17 which couples the table to the drive sleeve and inserting the key 47, whereupon the sleeve will be coupled to the piston and the'latter by its keyed engagement at 27 in the cylinder will serve to transmit rotation to the cylinder. In this way power may be applied to the cylinder either for the .purpose of unscrewing or screwing it into its seat, the shearing pins 52 being removed during these operations.

The lower thrust shoulder on the table sleeve is shown provided by a ring 53'screw threaded over the lower end of this sleeve and when a plain bearing is used at this point, as indicated, such bearing may be v simply in the form of a ring of bearing 'metal seated against a shoulder 54 at the lower end of the table bearing and engaged directly by the thrust ring 53. In similar fashion, the thrust shoulder 36 at the lower end of the drive sleeve may consist simply of a ring screw threaded into the lower end of said sleeve, as shown.

To enable the apparatus being quickly changed yover from the pressure feed to a straight rotary, the table may be constructed as shown, with a substantially angular seat 55 about the cylindrical bore therein, of a size to receive the adapters and slips ordi-,

narily used in rotaryi boring operations, which seat may be closed by an angular floor ring 56 when using the pressure feed. Thus when the apparatus is to be converted to the straight rotary, it is only necessary to lift out the pressure feed cylinder, piston and drive sleeve and the filler 56, whereupon the adapters, slips, etc., may be mounted in the table and used in' the regular way. Because of its long deep bearing, the table operates as a superior rotary and is capable of handling great lengths of drill stem.

In the present illustration, the liller 56 has an additional function in that it covers the drive keys 17, holding them down in their seats so that they cannot lift with the drive stem.

What is claimed is:

1. In well drilling apparatus, a rotary table having a large diameter bore therethrough for the drill pipe and casing, an

overall diameter less than the bore of said table and removable in its entirety means for removably supporting said power cylinder below the table and in line with the bore thereof, an annular piston operating in said cylinder and having a piston rod` projecting directly upwardly therefrom, a largediameter drive sleeve slidingly keyed in the bore of the table and having a relatively rotatable connection with sald upwardly extending piston rod, said drive sleeve being removable up through the table in its attached relation to the piston of the power cylinder and forming therewith a part of the same power unit.

2. In well drilling apparatus, a rotary table, a drive sleeve slidingly keyed in said table, an annular power cylinder, an annular piston therein for raising and lowering said drive sleeve, said power cylinder being insertible into and withdrawable from said rotary table, a bearing for the rotary table, the annular power cylinder having a detachable connection with and supported from said bearing.

3. In well drilling apparatus, a rotary t-able, a drive sleeve slidi'ngly keyed in said table, an annular power cylinder, an annular piston therein for raising` and lowering said drive sleeve, said power cylinder being insertible into and withdrawable from said rotary table, a bearing for the rotary table, the annular power cylinder having a detachable connection with and supported from said bearing, said. bearing being vertically 4elongated and the table having an elongated sleeve seating in said elongated bearing.

4. In well drilling apparatus, a rotary table having a large diameter bore therethrough for the drill pipe and casing, an annular power cylinder having an external overall diameter less than the bore of said table and removable in its entirety up through the bore of said table, means for removably supporting said power cylinder below the table and in line with the bore thereof, an annular piston operating in said cylinder and having a piston rod projecting directly upwardly therefrom, a large diameter drive sleeve slidingly keyed in the bore of the table and having a relatively rotatable connection with said upwardly extending piston rod, 1said drive sleeve being removable up through the table in its attached relation to the piston of the power cylinder and forming therewith a part of the same power unit, the bore in the table being provided by an elongated dependent bearing sleeve, thrust bearings at the upper and at the lower ends of said. elongated bear-- ing sleeve in widely separated relation and the relatively rotatable connections between the piston and drive sleeve comprising reversely acting thrust bearings in widely separated relation at the upper and at the lower ends of said drive sleeve.

5. In well drilling apparatus, a rotary table, a drive sleeve slidmgly-keyed in said.

table, an annular power cylinder, an annular` piston therein for raising and lowering sald drive sleeve, said power cylinder being insertible into and withdrawablo from sald rotary table,'the keyin connection between the table and sleeve eing releasable to enable independent rotation of the table and releasable means for securing the sleeve against rotation.

6. In welldrilling apparatus, a rotary table, a drive sleeve slidingly keyed in said table, an annular power cylinder, an annular piston therein for raising and lowering said drive sleeve, said power cylinder beinginsertible into and withdrawable from sald rotary table, the keying connection between the table and sleeve being releasable to enable independent rotationof the table and releasable means for ,securing the sleeve against rotation, including a detachable connection with the piston and means for holding the piston against rotation in thev cylinder.

7. In Well drilling apparatus, a rotary table, a bearing for supporting the same, an annular cylinder supported by said bearing, an annular piston operating in saidcylinder and held against rotation therein, a drive sleeve slidingly keyed in the table and a relatively rotatable power applying connection between the annular piston and drive sleeve, the keying connection between the table and sleeve being releasable to permit independent rotation of the table and releasable means for fixing the drive sleeve to the piston.

8. In well drilling-apparatus, a rotary table having'aseat for the adapters and slips used in rotary drilling operations, a drill stem drive sleeve removably engageable in" the bore of the table, means for slidably keying said drive sleeve in the table and a cover engageable in the adapter seat over said keying. means.

9.'In well drilling apparatus, a rot-ary table having an angular seat for used invrotary drilling operations, a drill stem driving sleeve removably engageable in the bore of the table, a removable key connecting the table and sleeve, power means for raising and lowering the drive sleeve and holding means for the key removably engageable in the adapter seat.

10. In well drilling apparatus, a rotary the adapters n' table having a large diameter bore therethe drill pipe and casing, an

- thereof, an annular piston operating in sai belov;7 the table and in line with the bore cylinder and having a piston rod projecting directly upwardly therefrom, a large dia-meter drive sleeve slidingly keyed in the bore of the table and having a relatively rotatable connection with said upwardl extending piston rod, said drive sleeve eing removable up through the table in its attached relation to the piston of the power cylinder and forming therewith apart of the same power unit, the drive sleeve being of larger diameter than the drill pipe and drill pipe engaging devices seated within the upper 'end of said larger diameter drive sleeve for gripping the smaller diameter drill pipe eX- ,tending therethrough.

11. In well drilling apparatus, a rotary table. having a seat-'for the adapters ordinarily employed in rotary drilling operations, a removable drill stem driving sleeve having a sliding driven engagement in the table andA a power sleeve for shifting said drive means vertically. with respect to the table and removable fromA the table with` the drive sleeve as an entity.

12. In well drilling apparatus, a table base having an elongated bearing provided at the lower end of the same with va seat, a rotary table having an elongated bearing sleeve engaged in said elongated bearing, an annular power cylinder removably engaged with the seat at the lower end of the bearing and removable up through the bore of the rotary table,'an annular piston in said cylinder and a drill stem driving sleeve keyed in the bore of the table and actuated by said power cylinder piston.

13. In well drilling apparatus, a table base having an elongated bearing provided at the lower end of the same with a seat, a rotary table having an elongated bearing sleeve engaged in said elongated bearing,

an annular power cylinder removably 'engaged with the seat at the lower end of the bearing and removable up through the bore of the rotary table, an annular piston in said cylinder and a drill stem driving sleeve 'keyed in the bore of the table and actuated by said power cylinder piston, said drive f, sleeve being disconnectible from driven engagement with the table and means for securing said sleeve against rotation in the table.

14. In well drilling apparatus, a table bas having an elongated bearing provided at the lower end of the same with a seat, a rotary table having an elongated bearing sleeve engaged in said elongated bearing, an annular power cylinder removably engaged with the seat at the lower end of the bearing and removable up through the bore of the rotary table, an annular pistonin said cylinder and a drill stem driving sleeve keyed in the bore of the table and actuated by said power cylinder piston, the seat for d the power cylinder comprlsing a `screw ring removably held to the lower end of the elongated bearing.

15. In well drilling apparatus, a rotary table having a seat for the adapters ordinarily employed in rotary drilling operations, a removable drill stem driving sleeve having a sliding driven engagement in the table, power means for shifting said drive leasable means for keying the sleeve in the table and a member engageable in the adapter seat over said releasable keying means.

16. In well drilling apparatus, a rotary table, a concentrically disposed power cylinder, an annular piston operating in said cylinder and heldagainst rotation therein, a drive sleeve slidably keyed in the table and releasable from keyed engagement therewith, a relatively rotatable power applying connection between the annular piston and drive sleeve and releasable means for nonrot-atably fixing the drive sleeve to the nonrotating piston.

17. In well drilling apparatus, a rotary table, a drive sleeve releasably keyed in said table, drill stem engaging means carried by said sleeve, a power cylinder, a piston in said cylinder having a power applying connection with said drive sleeve for raising and lowering the same irrespective of rotation of the table and means for securing said drive sleeve against rotation when the same is released from the table.

18. In well drilling apparatus, a rotary table, a drill stem driving sleeve operable vertically in said table, means for slidably keying said sleevein the table and readily releasable to permit the sleeve to remain stationary while the table rotates, an annular cylinder supported below the table and having an upwardly projecting inner cylinder wall, an annular piston' operating in said cylinder and having an annular piston rod operating up over said inner cylinder wall, keying means between said cylinder wall and piston rod, readily releasable keying means between the drive sleeve and piston rod and thrust transmitting connections between the piston rod and drive sleeve.

19. In well drilling apparatus, a rotary table, a `concentrically mounted drill stem driving sleeve, a power cylinder, a piston in said cylinder having a relatively rotatable connection with said sleeve for raising and lowering the same in the rotary table, a vertical key entered between the table and drive sleeve for releasablyv keying said drive sleeve in the table whereby said drive sleeve may -be caused to rotate with the table o r remain at rest in respect thereto and a readi' v sleeve vertically with respect to the table, re- 4 venting accidental release of said keying means, said securing device comprising a ring surrounding the ,drive sleeve and overstanding said key.

20. In well drilling apparatus, a rot-ary table, a concentrically mounted drill stem driving sleeve, a power cylinder, a piston in s aid cylinder having a relatively rotatable connection with said sleeve for raising and lowering the same in the rotary table, means for releasably keying said drive sleeve in the table whereby said drive sleeve may be caused to rotate with the table or remain at rest in respect thereto and releasable means for positively securing the sleeve 'against rotation with the table.

21. In well drilling apparatus, a rotary table having a bore therethrough, a base for rotatably supporting said table, an annular power cylinder of less diameter than the bore of said table, means on the base for detachably supporting said cylinder below the table in line with the borev therethrough, a piston in said cylinder having an annular piston rod extending up into the bore of the table and a drill stem drive sleeve engaged by said piston rod and having a detachable keyed engagement in the table whereby said drive sleeve, power cylinder and piston may be lifted out of the table as a unit.

22. In well drilling apparatus, a rotary tablehaving a bore therethrough, a base for rotatably supporting said table, an annular power cylinder of less diameter than the bore of said table, means on the base for detacliably supporting said cylinder below the table in line with the bore therethrough, a piston in said cylinder having an annular piston rod extending up into the bore of the table and a drill stem drive sleeve enga ed by said piston rod and having a detacha le keyed engagement in the table whereby said' drive sleeve, power cylinder and piston may be lifted out ofthe table as a unit, said table having a seat about the bore therethrough for the adapters ordinarily employed in the rotary` drilling operations and enabling such use of the table when the power unit is removed and means applicable as a cover over said seat when the drive sleeve is in use, said detachable keying means being disposed beneath and protected by said cover.

23. In well drilling apparatus, a rotary table, a drive sleeve releasably keyed in said table, an annular power cylinder, an annular piston in said cylinder having an annular piston rod extendin up inside said drive sleeve, relatively rotatale power applying connections between said piston rod and sleeve, said sleeve havin a portion projecting over the upper e'ndo the piston rod and releasable keying means between said overstanding portion of the sleeve and the piston rod.

24. In well drilling apparatus, a rotary table, a drive sleeve slidably mounted in said table, an annular cylinder, a screw seat with which said cylinder is removably en aged, a piston operating in said cylinder and having a thrust transmitting the drive sleeve and means for coupling the cylinder with the rotary table so that rotabe effective to turn the connection withi cylinder with the rotary table so that rotation of the latter will be effective to turn the cylinder in its screw seat, including means for keying the rotary table to the drive sleeve, the drive sleeve to the piston and the piston to the cylinder.

26. In well kdrilling apparatus, a rotary table, a drive sleeve slidably mounted in said table, an annular cylinder, a screw seat with which said cylinder is removably engaged, a piston operating in said cylinder and having a thrust transmitting connection with the drive sleeve and means for coupling the cylinder with the rotary table so that rotation of the latter will be eifective to turn the cylinder in its screw seat, including means for. keying the rotary table to the drive sleeve, the drive sleeve to the piston and the piston to the cylinder, the ke ing .means be'- tween table and sleeve and tween sleeve and piston being readily releasable.

27. In well drilling apparatus, a base, a rotary table journaled in said base, a supporting ring mounted on said base at the foot of said table, an annular cylinder removably seated in said ring, a piston operating in said cylinder having an upwardly projecting piston rod and a drive sleeve keyed in the table and having a thrust connection with the piston rod.

28. In well drilling apparatus, a rotary table having a dependent sleeve, an annular cylinder, ascrew seat for'said cylinder at the foot of said sleeve, said cylinder being removable from said screw seat upwardly through said sleeve, a drive sleeveslidably keyed in the table sleeve and a piston in the cylinder having a piston rod connected in power applying relation to the drive sleeve.

29. In well drilling apparatus, a base, a rotary table journaled in said base, a supportin ring mounted on said base at the foot 0% said table, an annular cylinder re` movably seated in said ring, a piston operating in said cylinder having an upwardly projecting piston rod and a drive sleeve keyed in the table and having a thrust connection with the piston rod, said supporting ring being an internally screw threaded ring, the cylinder being screw threaded to it the same and means for removably mounting said ring on the base.

30. In well drilling apparatus, a base, a rotary table journaled in said base, a su porting ring mounted on said base at t e oct of said table, movably seated in said ring, a piston operating in said cylinder having an upwardly 10 projecting piston rod, a drive sleeve keyed in the table and having a thrust connection with the piston rod and means for coupling the cylinder in driven engagement with the rotary table whereby the latter may be utilized to break the cylinder from its seat.

31. In well drilling apparatus, a rotary table having a large diameter bore therethrough for the drill pipe and casing, an annular power cylinder having an external overall diameter less than the bore of said table and removable in its entirety up through the bore of said table, means for removably supporting said power cylinder below the table and in line with the bore thereof, an annular piston operating in said cylinder and having a piston rod projecting directly upwardly therefrom, a large diameter drive' sleeve slidingly keyed in the bore of the table and having a relatively rotatable connection with said upwardly eX- tending -piston rod, said drive sleeve being removable up through the table in its attached relation to the piston of the power cylinder and forming therewith apart of the same power unit, the bore in the table being provided by an elongated dependent sleeve,

a base for supporting the table having a dependent Qelongated sleeve receiving the table sleeve, the power cylinder being removablyV attached to the lower end of said base vsleeve and bearings for the table in widely separated relation at'the upper and lower ends of saidbase sleeve.

32. In well drilling apparatus, a rotary table, a* base for supporting the same, an

annular power cylinder and means operated thereby for imparting lifting or lowering force to a drill stem rotated by the table,

an annular support for said cylinder and a sectional clamp for securing said annular support to the base, the base having an annular portion with a groove therein and the clamp having a portion engaged with said groove for holdingit to the base.

33. In well drilling apparatus, a rotary table having a dependent` large diameter bearing sleeve providin a lpassage therethroug a drill stem drive sleeve slidingly ided in said table sleeve and keyed to turn with the table, an annular power cylinder supported below the table and having an inner annular cylinder wall extending up within the drive sleeve, an annular piston operating in said power cylinder and connected B5 with the drive sleeve for raising and loweran annular cylinder re-v ing the same, means for keying the piston against rotation in the annular cylinder, a base having a seat for the support of said annular power cylinder, means for securing said cylinder against rotation in said seat, said securing means being releasable to permit rotation of the cylinder in its seat and means for effecting a coupling between the drive sleeve and piston, whereby rotation of the table may be utilized to impart rotation to the piston and to the cylinder to which it is keyed.

34. In table having a dependent large diameter bearing sleeve providing a passage therethrough, a drill stem drive sleeve slidingly guided in said table sleeve and keyed to turn with the table, an annular power cylinder supported below the table and having an inner annular cylinder wall extending up within the drive sleeve and an annular piston operating in said power cylinder and connected with the drive sleeve for raising and lowering the same, the drive sleeve being of larger internal diameter than the drill stem and drill stem gripping devices seated in the upper end of said drive sleeve and the annular power cylinder being of less diameter than the inside diameter of the bearing sleeve of the table, whereby the drive sleeve carrying the drill stem gri ping devices, the annular piston and the cy inder may all be lifted from the bearing sleeve of the table.

35. In well drilling apparatus, a base carrying an elongated large diameter bearmg sleeve, a rotary tab e having a large diameter long sleeve operating in the bearing sleeve of the base, thrust bearings at the upper and lower ends of said sleeves for carrying vertical thrust loads on the table in both directions, a large diameter drill stem drive sleeve slidingly keyed within the table sleeve, drill stem gripping means detachably mounted in the upper end of said drive sleeve, an annular power cylinder concentrcallyA mounted below the table, an annular pistn operating within said annular cylinder, an annular piston rod connected with said annular piston and extending up over the outside of the inner annular wall of the cylinder said annular iston rod extending up within the drive s eeve and connected therewith for raising and lowering the same within the sleeve of the table, a seat to the lower end of the sleeve carried by the base and said power cylinder having a removable mountln in said seat.

56. In well dr' apparatus, a base carrying ,an elongatedv arge diameter bearing sleeve, a rotary table having a large diameter long sleeve operating in the bearing sleeve of the base,'thrust bearings at the upper and lower ends of said sleeves for carrying verwell drilling apparatus, a rotary Afor the power cylinder removably attached tical thrust loads on the table in both directions, a large diameter drill stem drive sleeve slidingly keyed within the table sleeve, drill stem gripping means detachably mounted in the upper end of said drive sleeve, an annular power cylinder concentrically mounted below the table, an annular piston operating within said annular cylinder and an annular piston rod connected with said annular piston and extending up over the outside of the inner annular wall of the cylinder, said annular piston rod extending up within the drive sleeve and connected therewith for raising and lowering the same within the sleeve of the table, the power cylinder being of less diameter than the table sleeve and being removably supported below said sleeve so that the same may be readily withdrawn as a unit up through the table sleeve without disturbing the mounting of the table in the base.

37. In well drilling apparatus, a rotary table, a drive sleeve operating vertically in said table, means for releasably keying said sleeve in the table, whereby it may be driven by the table or remain in non-rotating relation thereto, power mechanism for positively raising and lowering the drive sleeve in the rotary table, drill pipe grip means carried by said drive sleeve and releasable means for securing .said drive sleeve fast against rotary movement when uncoupled from the rotary table. v

38. In well drilling apparatus, a base, a rotary table journaled in said base, a power cylinder supported rotatably on the base, a drill pipe driving member slidingly keyed to rotate with the table, connections from the power cylinder for positively raising and lowering t-he drive sleeve in the table and means for eecting non-rotating connections from the drive sleeve to the cylinder, whereby the rotation of the table may be imparted to the power cylinder.

39. In well drilling table, a non-rotating annular power cylinder below the same and having an inner annular cylinder wall, a piston in said cylinder and having an annular pis/ton rod extending up apparatus, a rotary over the inner annular cylinder wall, keying v means between said annular piston rod and inner cylinder wall,

whereby said piston is held against rotation in the cylinder, a drive sleeve in the table, relatively rotative connections between said drive sleeve and annular piston rod, means for slidably keying the drive sleeve in the table and means for keying the drive sleeve to the piston, both said keying means being releasable, whereby said drive sleeve may be held non-rotating while thetable rotates when the drive sleeve is unkeyed from the table and keyed to the piston and whereby the'drive sleeve may be caused to rotate with the table and the piston will remain stationary when the drive sleeve is keyed to the table and unkeyed from the piston.

40. In well drilling apparatus, a rotary table, an annular power cylinder below the same and having an innerl annular cylinder wall, a piston in said cylinder and having an annular piston rod extending up over the inner annular cylinder wall, keying means between said annular piston rod and inner cylinder wall, whereby said piston is held againstrotation in the cylinder, a drive sleeve slidingly keyed in the table, relatively rotative connections between said drive sleeve and annular piston rod and means for coupling the drive sleeve in non-rotative relation lto the annular piston rod.

41. In well drilling apparatus, table having a bore therethrough, a driving sleeve .slidingly keyed in and withdrawable therefrom, a inder removably supported below the table, said power cylinder being of less diameter than the bore of the table and withdrawable upwardly therethrough and a piston operating in said c linder and having a piston rod connectedwith the drive sleeve for raising and lowering the same inthe table.

In witness whereof, I have lhereunto set my hand this 8th day of May, 1924.

WALDO SHELDON.

a rotary drill pipe said table power cyl- 

